GM Testing Volt's Battery, iPhone-like Dash on Track to 2010

Here at GM's top-secret Technical Center lies the high-tech bones of the Chevrolet Volt, which is looking more and more like it'll be in dealerships by 2010.

WARREN, Mich. -- The future of General Motors' advanced, plug-in electric hybrid vehicle program might seem like a tired-looking, maroon-colored 2005 Chevy Malibu, but that's just a disguise. Underneath the test mule's pedestrian sheet metal here at GM's top-secret Technical Center lies the high-tech bones of the Chevrolet Volt, which is looking more and more like it'll be in dealerships by 2010.

It's easy to get excited about the Volt. It could be America's first production plug-in hybrid after all, and the specs are impressive: 40 mi. of all-electric cruising before a small gasoline engine steps in to charge the battery, extending driving range to any where to 350 to 400 miles. But it's still not quite set for prime time, with GM testing a nickel-metal hydride unit in the Volt because the right lithium-ion packs weren't ready for the road. But that's all changed now.

Right here, right now, in this lab, GM is testing two batteries in what amounts to a horse race for the future of driving: a nonophosphate unit with cylindrical cells from A123 Systems and large, stacked wafers of manganese oxide from Compact Power, a division of LG. The new battery packs are currently being installed as hundreds of engineers work around the clock, and a fleet of mules will test them at various GM proving grounds around the country by summer.

If each tests well, though, Rocky Mountain Institute vice president Michael Brylawski says GM might as well use both packs: "This is high-risk technology. What if something goes wrong on one battery production line?" The goal is to meet GM's 16-kw power target, that 40-mi. cruise and a 10-year, 150,000-mi. service life. Oh yeah, and hit 0-60 mph in 8.5 seconds with a top speed of 100 mph.

The Volt's chassis, meanwhile, was thought to offer a unique architecture developed solely for the Volt and its future E-Flex stablemates--not true. The Volt will use the next-gen "Delta" platform for small cars found underneath vehicles like the Chevy Cobalt, with a beam-type rear axle featuring coil springs and McPherson struts upfront. The internal combustion engine rides up front, as expected, but occupies only half the engine room. Much of the development for the hybrid electronics, comes from lessons GM learned from its Two-Mode hybrid program, said chief E-Flex engineer Frank Weber, also suggesting that that the Volt might share some electrical components with Two-Mode.

The T-shaped battery pack rides low in the chassis beginning where the transmission tunnel would be on a conventional vehicle. And the top of the pack's "T" ends underneath the rear seats (watch video of the Volt's guts here). The pack intrudes into the passenger cabin, so GM decided to make the Volt a four-seater instead of raising the roof line to accommodate that middle seat. And the battery pack itself, GM says, is a structural element in the chassis with four large gussets on the bottom. Another challenge? Thermal management. Mounted behind the conventional radiator, then, stands a thick stack of four separate coolers and two sophisticated electric fans.

In order to save weight and room to package components, GM engineers reduced the size of the gas tank, which is positioned behind the battery pack. And that dropped the range from the projected 640 to more like 400. The electric power steering rack will likely be a common component across the Delta platform along with the suspension, floor pan and front drive axles. The 120-kw electric motor won't come paired to a transmission, running instead through a fixed-speed gearset and on to the wheels.

The Volt's aerodynamics are even more important for fuel economy to than weight. "This vehicle spent more time on our wind tunnel than any current project GM," Weber said. His modeling indicates that 200 pounds saved by expensive lightweight components would give the Volt just two or three extra miles of EV range. So the plug-in won't use flashy carbon-fiber fenders, magnesium structural braces or polycarbonate windows, but an updated aero profile from the original concept's sheet metal.

In the design studio, E-Flex design director Bob Boniface showed us the production car's corners. The front end is very smooth and rounded, kind of like a Honda Civic, while the rear take cues from the Toyota Prius with its high, hatchback trunk. But the rear deck spoiler is much larger, and the taillamps look very similar to the concept. The overall shape, which was covered by a red sheet in the studio, looked to have a very Prius-like profile. In other words, the proportions and overall style of the Volt probably won't look much like the concept.

Inside, the Volt looks spacious, with a techie attitude. The interior designers had to move the front seats outward a bit to clear the large center hump of the battery box, so the door skins were thinned by 12 to 15 mm in certain places to make room. The center stack is reminiscent of the new Cadillac CTS, and, get this, Weber promises the Volt will provide an iPhone-like touchscreen interface between driver and vehicle. A large display screen will likely be standard and allow owners to custom-tailor certain driving and charging parameters. For example, he says you could plug in your car at home and then program it to charge, say five hours later, when off-peak power is cheapest. Sustainable materials are all over the place, from a recycled carpet to soy-based foam seats.

It's obvious that GM is very serious about the Chevy Volt--Warren said "nothing gets in the way of this car" like he meant it. The progress so far is impressive, but we'll have to wait for a turn behind the wheel to find out if all this hard work has been worth the effort.

A Part of Hearst Digital Media
Popular Mechanics participates in various affiliate marketing programs, which means we may get paid commissions on editorially chosen products purchased through our links to retailer sites.